Rotary switch



Aug. 30, 1960 H. F. MASON 2,951,130

ROTARY SWITCH Filed May 5, 1959 6 FIG. 1.

INVENTOR HOWARD E MASON BY H/S ATTOEA/b'YS HARE/5, K/ECH, Russell.(2/1150 Unite ROTARY swrrcn Filed May 5, 1959, Ser. No. 811,091

'10 Claims. (Cl. 200-457) The present invention relates in general torotary switches and, more particularly, to a rotary switch whichoperates with a snap action, produced by energy stored in a spring orspring system, to make and break contact quickly so as to minimizearcing, which operates in a positive manner in that the movable contactsnaps from one operative position to another without any possibility ofhesitating between such positions, which operates in this mannerirrespective of how the switch may be manipulated by its operator andirrespective of vibration, which provides a positive feel? sothat, whenthe switch is operated manually, the operator can readily determine thatthe switch has advanced from one'operative position to another, and thelike.

Still more particularly, the invention relates to a rotary switchsimilar to those of my Patents Nos. 2,831,073 and 2,831,082, bothgranted April 15, 1958, a general object of the invention to provide aswitch which is an improvement on those disclosed in such patents.

Considering therotary switch of the present invention in a general way,it includes: an arcuate contact path having a center of curvature andhaving circumferentially spaced recesses therein .and having thereon atleast one stationary contact in which one of the recesses is formed,there normally, but not necessarily, being a stationary contact at eachrecess; a contact carrier movable about the center of curvature along, acarrier path adjacent and concentric with the contact path; a rollercontact carried by the contact carrier, and engaging and rollable alongthe contact path and receivable -in each of the recesses therein;resilient means engaging the roller contact and biasing same intoengagement with the contact path; actuating means for moving the contactcarrier along the carrier path; and means providing a resilientlost-motion connection between the actuating means and the contactcarrier for transmitting rotation of the actuating means to the contactcarrier after limited rotation of the actuating means, such lost-motioncon nectionresulting in energy storage which causes the roller contactto snap from one recess to the next when the roller contact is forcedout of the first recess after using up the lost motion between theactuating means and the contact carrier. a

A primary object of the invention is to provide a rotary switch of theforegoing nature having cam means on the contact carrier for moving theroller contact radially out of arecess-in which it is disposed inresponse-to movement of the contact carrier along the carrier path bythe actuating means, such cam means overcoming at least partially theresilient means biasing, the roller contact into engagement with thecontact path.

The foregoing is an importantfeature since it peratent contact pressurecan be quite high when the roller contact is disposed in one of therecesses, which is desirable but this high contact pressure is reducedby the cam means when the roller contact is to be moved out of suchrecess and into the next one, thereby facilitating operation of theswitch.

Another object of the invention is to provide the con tact carrier witha cam surface inclined at an acute angle to the contact path and adaptedto move the roller contact radially out of a recess in which it isdisposed in response to movement of the contact carrier along thecarrier path.

Another object is to provide the contact carrier with two cam surfacesconverging toward and inclined at acute angles to the contact path, oneof these cam surfaces camming the roller contact out of the recess inwhich it is disposed in response to movement of the contact carrier inone direction, and the other cam surface achieving the same result inresponse to movement of the contact carrier in the opposite direction,thereby providing a cam means which operates in both directions of.movement of the contact carrier.

A further object is to provide a construction wherein the roller contacthas an axle which is engageable by the cam surfaces mentioned and whichis engaged by the resilient means for biasing the roller contact intoengagement with the contact path. I

Still another object is to provide a construction wherein the resilientmeans for biasing the roller contact comprises torsion springs eachhaving an arm engaging the contactcarrier and another arm engaging theaxle of the roller contact.

V The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults thereof which will be evident to those skilled in the rotaryswitch art in the light of this disclosure, may be achieved with theexemplary embodiment described in detail hereinafter and illustrated inthe accompanying drawing, in which:

Figs. 1 to 5 are semidiagrammatic, transverse sectional views of arotary switch embodying theinvention and showing various componentsthereof in successive operatmits avery high contact pressure betweentheroller .con-

ing positions; and

Fig. 6 is a longitudinal sectional view taken along the arrowed line 66of Fig. 1.

In the drawing, the numeral 10 designates a rotary switch of theinvention which is more properly termed a toggle switch since itsoperating range is only a small segment of a circle. However, it will beunderstood that the operating range of the switch 10 may be increased upto and including 360, as shown in my aforementioned patents. Also,various of the structural fea tures disclosed in such, Patents may beincorporated in the switch 10, it being understood that much of thestructure of the switch 10 is illustrated semidiagrammatically forconvenience.

Considering the switch 10 in more detail, it includes a case or housing12 which provides anarcuate contact path 14 having its center ofcurvature at 16. The con: tact path 14 is provided with arcuate recesses18, 20 and 22 therein which are directed radially inwardly toward thecenter of curvature 16. In the particular constructionillustrated, theswitch 10 includes a number ofstationary contacts equal to the number ofrecesses, the stationary contacts respectively being designated by thenumerals 24, 26 and 28 and respectively having the recesses 18, 20 and22 formed therein. However, it will be understood that not all of therecessesneed to be formed in stationary contacts. For example, if one ofthe recesses 18, 20 and 22 merely represents an off position, thecorresponding stationary contact may be omitted. Y

The stationary contacts 24, 26 and 28 are electrically insulated fromeach other, as by embedding them in electrical insulating material. Inthe particular construction illustrated, the entire housing 12 is formedof electrical insulating material and the stationary contacts 24, 26 and28 are embedded therein. As wi-llbe apparent, the contact path 14 isformed partially by the stationary contacts 24, 26 and 28 and partiallyby the electrical insulating material separating these contacts fromeach other.

As best shown in Fig. 6 of the drawing, each of the stationary contacts24, 26 and 28 includes two longitudinally spaced stationary contactelements electrically insu-lated from each other and adapted to bebridged by a roller contact 3% reliable along the contact path 14 andreceivable in each of the recesses 18, 20 and 22 therein. In theparticular construction illustrated, the roller contact 30 is similar tothe roller contact 32 of my Patent No. 2,831,073 and includes tworollercontact elements respectively engageable with the stationarycontact elements of each of the stationary contacts 24, 26 and 28 andinterconnected by an axle 32 which projects beyond the ends of theroller contact. However, it will be understood that the roller contact30 may, if desired, have the construction of the roller contact 25 of myPatent No. 2,831,082. This latter construction has the advantage thatthe stationary contacts 24, 26 and 28 and the electrical insulatingmaterial therebetween may be out of alignment to prevent the rollercontact 30 from tracking metal from the stationary contacts onto theintervening electrical insulating material.

The roller contact 30 is housed in a contact carrier 34 having sidewalls 36 respectively provided with notches or slots 38 respectivelyreceiving the ends of the axle 32. The inner ends of the slots 38communicate with triangular openings 40 respectively formed in the sidewalls 36 of the contact carrier 34 and respectively adapted to receivethe ends of the axle 32. Eachtriangular opening 40 is provided with twocam edges or surfaces 42 and 43 converging toward and making acuteangles with the contact path 14 and. engageable with the correspondingend of the axle 32. The cam surfaces 42 and 43 constitute a cam meansfor moving the roller contact 30 out of one of the recesses 18, 20 and22 in which it is disposed, as discussed in more detail hereinafter. I

The roller contact 30 is biased into engagement with the contact path 14andinto the recesses 18, 20 and 22 therein by a resilient means which isshown as comprising two torsion springs 44 respectively coiled aroundpins 46 on the contact carrier 34 and each having an arm 48 engaging thecontact carrier and another arm 50 engaging the axle 32. In theparticular construction illustrated, there are two of the springs 44 andthey engage the axle 32 intermediate the roller contact elements formingthe roller contact 30. However, it will be understood that if the rollercontact structure 25 of my Patent No. 2,831,082 is,nsed, there may befour of the springs 44, two engaging each end of the roller contactaxle.

The switch includes an actuating means 52 shown as comprising a lever 54having thereon a ball 56 the center of which coincides with the centerof curvature 16 and which is disposed in a diagrammatically-shown ballsocket 58 carried by the housing 12. It will be understood that thisrepresents merely one way of obtaining rotary motion about the center ofcurvature 16 and that such rotary motion may be achieved in other ways.For example, a shaft, not shown, may be substituted for the ball 56,particularly where 360 rotation of the roller contact 30 is desired. Thelever 54 is connected to the contact carrier 34 by a lost-motionconnection 60, which provides a range of relative rocking movementbetween the lever and the contact carrier at least approaching thespacing of the stationary contacts 24, 26 and 28 so that once movementof the roller contact 30 from one recess to the next begins, suchmovement is completed with little or no further movement of the lever 54to provide a positive action which cannot be interfered with by theoperator of the switch 10. Means 62 for limiting the relative rockingmovement between the lever 54 and the contact carrier 34 is provided.

Considering the lost-motion connection 60 in more detail, mounted on theinner end of the lever '54 within the housing 12 is an actuator 64engaging the contact carrier 34 through two tongue-and-grooveconnections which form the lost-motion connection 60. More specifically,in the particular construction illustrated, the actuator 64 is providedtherein with two parallel grooves 66 and 68 which extend transversely ofthe contact path 14 and which receive complementary tongues or ribs 70and 72, respectively, on the contact carrier 34. The means 62 forlimiting relative rocking motion between the actuator 64 and the contactcarrier 34 comprises stops or kickers 74 and 76 respectively engageablewith the ends of the contact carrier 34. 1

Considering the operation of the invention, it will be assumed that thecomponents of the switch 10 are in the positions shown in Fig. 1 of thedrawing and that the rollercontact 30 is to be moved from the recess 20into the recess 22. This is accomplished by a leftward force applied tothe outer end of the lever 54, which force produces the followingaction.

First, the actuator 64 "and the contact carrier 34 rock relative to eachother about the tongue-and-grooveconnection provided by the tongue 70and the groove 66 into the positions shown in Fig. 2. Such relativerocking of the actuator 64 and the contact carrier 34 has resulted inengagement of the kicker 74 with the left end of the contact carrier 34.This relative rocking has also resulted in engagement of the ends of theaxle 32 with the cam surfaces 42, the stress in the springs 44 havingbeen increased to some extent as the foregoing takes place.

Turning nowto Fig. 3 of the drawing, further leftw ard movement of theouter end of the lever 54 causes the kicker 74 to move the cont-actcarrier 34 toward the right. When this happens, the cam surfaces 42acting on the ends of the axle 32 lift the roller contact 30 out of therecess 20 and onto the raceway between the recesses 20 and 22 inopposition to the action of the springs 44. 7

Once the roller contact 30 is on the raceway between the recesses 20 and22, as shown in Fig. 4, the springs 44 start to rock the contact carrier34 back into its original position relative to the actuator 64. Thisrestoring action on the contact carrier 34 by the energy stored in thesprings 44 causes the roller contact 30 to roll along the racewaybetween the recesses 20 and 22 and into the recess 22 extremely rapidly.This has the eifect of minimizing arcing, and also has the eiiect ofinsuring that once the roller contact 30 leaves the recess 20, it willmove all the way into the recess 22 irrespective of any subsequentmanipulation of the lever 54.

It will be apparent that the switch 10 operates in the same manner whenthe roller contact 30 moves from the recess 18 to the recess 20. Theswitch operates in a similar manner when the roller contact 30 movesfrom the recess 22 into the recess 20, or from the recess 20 into therecess 18, except that the kicker 76 and the cam surfaces 43 operate,instead of the kicker 74 and the cam surfaces 42.

The most important feature of the invention is that the cam meansprovided by the cam surfaces 42 and 43 lifts the roller contact 30 outof each of the recesses 18, 20 and 22 in opposition to the action of thesprings 44, thereby reducing the operating force which would otherwisebe required'to kick the roller contact out of the recess in which it isdisposed. Consequently, for the same operating force, springs 44producing greater spring forces may be utilized to attain the maximumpossible contact pressure between the roller contact 30 and thestationary contacts 24, 26 and 28. Thus, the invention has the efiect ofmaximizing the contact pressure while minimizing the operating forcerequired.

Although an exemplary embodiment has been disclosed herein for purposesof illustration, it will be understood that various changes,modifications and substitutions may be incorporated in such embodimentwithout departing from the spirit of the invention as defined by theclaims which follow.

I claim:

1. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses is formed; a contact carrier movable aboutsaid center of curvature along a carrier path adjacent and concentricwith said contact path; actuating means movable about said center ofcurvature for moving said contact carrier along said carrier path; aroller contact carried by said contact carrier and engaging and rollablealong said contact path and receivable in each of said recesses; means,including resilient means, acting on said roller contact for biasingsaid roller contact into engagement with said contact path; and cammeans on said contact carrier and engageable with said roller contactfor moving said roller contact out of one of said recesses in which itis disposed in response to movement of said contact carrier along saidcarrier path by said actuating means.

2. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses is formed; a contact carrier movable aboutsaid center of curvature along a carrier path adjacent and concentricwith said contact path; actuating means movable about said center ofcurvature for moving said contact carrier along said carrier path; aroller contact carried by said contact carrier and engaging and rollablealong said contact path and receivable in each of said recesses, saidroller contact having an axle; means, including resilient means, actingon said axle for biasing said roller contact into engagement with saidcontact path; and cam means on said contact carrier and engageable withsaid axle for moving said roller contact out of one of said recesses inwhich it is disposed in response to movement of said contact carrieralong said carrier path by said actuating means.

3. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses is formed; a roller contact engaging androllable along said contact path and receivable in each of saidrecesses, said roller contact having an axle; a contact carrier for saidroller contact movable about said center of curvature along a carrierpath concentric with and adjacent said contact path, said contactcarrier having thereon cam means engageable with said axle for movingsaid roller contact radially out of one of said recesses in which it isdisposed in response to movement of said contact carrier along saidcontact path, said cam means including a cam surface engageable withsaid axle and inclined at an acute angle to said contact path; means,including resilient means, acting on said contact carrier and said axlefor biasing said roller contact into engagement with said contact pathand into one of said recesses in which it is disposed in opposition tothe action of said cam means; and actuating means movable about saidcenter of curvature for moving said contact carrier along said carrierpath.

' 4. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses is formed; a roller contact engaging androllable along said contact path and receivable in each" of saidrecesses, said roller contact having an axle; a contact carrier for saidroller contact movable about said center of curvature along a carrierpath concentric with and adjacent said contact path, said contactcarrier having thereon cam means engageable with said axle for movingsaid roller contact radially out of one of said recesses which it isdisposed in response to movement of said contact carrier along saidcontact path, said cam means including two inclined cam surfaces whichconverge toward and make acute angles with said path and which areselectively engageable with said axle; means, including resilient means,acting on said contact carrier and said axle for biasing said rollercontact into engagement with said contact path and into one of saidrecesses in which it is disposed in opposition to the action of said cammeans; and actuating means movable about said center of curvature formoving said contact carrier along said carrier path.

5. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses'is formed; a roller contact engaging androllable along said contact path and receivable in each of saidrecesses, said roller contact having an axle; a contact'carrier for saidroller contact movable about said center of curvature along a carrierpath concentric with and adjacent said contact path, said contactcarrier having thereon cam means engageable with said axle for movingsaid roller contact radially out of one of said recesses in which it isdisposed in response to movement of said contact carrier along saidcontact path, said cam means including two inclined cam surfaces whichconverge toward and make acute angles with said path and which areselectivelyengageable with said axle;

means, including resilient means, acting on said contact carrier saidaxle for biasing said roller contact into engagement with said contactpath and into one of said recesses in which it is disposed in oppositionto the action of said cam means; actuating means movable about saidcenter of curvature for moving said contact carrier along said carrierpath; means providing a lost-motion connection between said actuatingmeans and said contact carrier; and kicking means carried by saidactuating means and engageable with said contact carrier for limitingthe lost motion between said actuating means and said contact carrier soas to kick said roller contact out of one of said recesses in which itis disposed.

6. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses is formed; a roller contact engaging androllable along said contact path and receivable in each of saidrecesses, said roller contact having anaxle; a contact carrier for saidroller contact movable about said center of curvature along a carrierpath concentric with and adjacent said contact path, said contactcarrier having thereon cam means engageable with said axle for movingsaid roller contact radially out of one of said recesses in which it isdisposed in response to movement of said contact carrier along saidcontact path, said cam means including two inclined cam surfaces whichconverge toward and make acute angles with said path and which areselectively engageable with said axle; means, including resilient means,acting on said contact carrier and said axle for biasing said rollercontact into engagement with said contact path and into one of saidrecesses in which it is disposed in opposition to the action of said cammeans; actuating means movable about saidcenter of curvature for movingsaid contact carrier along said carrier path; means providing alost-motion connection between said actuating means and said contactcarrier, said lost-motion connection including means providing relativerocking movement between said actuating means and said contact carrier;and kicking means carried by said actuating means and engageable withsaid contact carrier for limiting the lost motion between said actuatingmeans and said contact carrier so as to kick said roller contact out ofone of said recesses in which it is disposed.

7. In a rotary switch, the combination of: an arcuate contact pathhaving a center of curvature and having circumferentially spacedrecesses therein and having thereon at least one stationary contact inwhich one of said recesses is formed; a roller contact engaging andreliable along said contact path and receivable in each of saidrecesses, said roller contact having an axle; a contact carrier for saidroller contact movable about said center of curvature along a carrierpath concentric with and adjacent said contact path, said contactcarrier having thereon cam means engageable with said axle for movingsaid roller contact radially out of one of said recesses in which it isdisposed in response to movement of said contact carrier along saidcontact path, said cam means including two inclined cam surfaces whichconverge toward and make acute angles with said path and which areselectively engageable with said axle; means, including resilient means,acting on said contact carrier and said axle for biasing said rollercontact into engagement with said contact path and into one of saidrecesses in which it is disposed in opposition to the action of said cammeans, said resilient means including torsion springs carried by saidcontact carrier and each having an arm engaging said contact carrier andanother arm engaging said axle; actuating means movable about saidcenter of curvature for moving said contact carrier along said carrierpath; means providing a dost-motion connection between said actuatingmeans and said contact carrier, said lost-motion connection includingmeans providing relative rocking movement between said actuating meansand said contact carrier; and kicking means carried by said actuatingmeans and engageable with said contact carrier for limiting the lostmotion between said actuating means and said contact carrier so as tokick said roller contact out of one of said recesses in which it isdisposed.

8. In a switch, the combination of: a structure providing a contact pathhaving spaced recesses therein and having thereon at least onestationary contact in which one of said recesses is formed; a contactcarrier movable along a carrier path adjacent said contact path;actuating means pivotable relative to said structure about a pivot axisfor moving said contact carrier along said carrier path; a rollercontact carried by said contact carrier and engaging and rollable alongsaid contact path and receivable in each of said recesses; means,including resilient means, for biasing said roller contact intoengagement with said contact path; and cam means for moving said rollercontact out of one of said recesses in which it is disposed in responseto movement of said actuating means about said pivot axis.

9. In a switch, the combination of: a structure providing a contact pathhaving spaced recesses therein and having thereon at least onestationary contact in which one of said recesses is formed; a contactcarrier movable along a carrier path adjacent said contact path;actuating means pivotable relative to said structure about a pivot axisfor moving said contact carrier along said carrier path; a rollercontact carried by said contact carrier and engaging and reliable alongsaid contact path and receivablein each of said recesses; means,including resilient means, for biasing said roller contact intoengagement with said contact path; means providing a lostmotionconnection between said actuating means and said contact carrier; andcam means for moving said roller contact out of one of said recesses inwhich it is disposed in response to movement of said actuating meansabout said pivot-axis.

a 10. A switch'according to claim 9 wherein said roller contactisprovided with an axle and wherein said cam means is engageable withsaid axle.

No references cited.

